Several methods have been employed to address the issue of foul odors emanating from a toilet. Previous attempts to address this issue have involved drawing the air from the bowl into the tank for treatment and disposal. Although much of the prior art relies on similar theories of design, the individual applications vary.
For example, U.S. Pat. No. 4,864,664 to Higgins describes a ventilated toilet having an air duct and water trap system for removing air contaminated with objectionable odors directly to a sewer line. The toilet bowl and tank have built-in air systems and the toilet seat is hollow and forms part of the air system. The fan and electrical components are located at the highest level of the fan-duct system so that water entering the air system due to tank overflow or a leak in the system will run out through the duct system before reaching the electrical components. The present system provides a water trap/air vent combination which does not rely on running water to refill the trap.
The '664 patent differs from the present invention in two significant respects however. First, air travels from the bowl to the tank through holes in the hollow seat, rather than using the pre-existing flush holes under the rim of the bowl. Secondly, the connection through which air travels to the sewer line is incorporated into the tank. This would make retrofitting unduly burdensome. It also creates a possibility of gases traveling from the sewer line into the tank.
Similarly, U.S. Pat. No. 4,103,370 to Arnold describes a toilet system with an intake manifold interposed between the seat and the top periphery of the bowl. A fan is arranged to draw air from the manifold and deliver it to the sewer connection beyond the water trap. The manner in which air passes from the bowl, through the intake manifold to the tank, is a significant departure from existing toilet design, making retro-fit impracticable.
Therefore, what is needed is an efficacious system of adapting a toilet to draw malodorous air from the area surrounding the bowl and disposing said air into the septic line. To be truly efficacious, the system would need to be inexpensive in its creation, as well as allow for the retrofitting of existing toilets.